Carton



United States Patent 3,327,922 CARTON Morris L. Netherton, Nashua, Mo., and David E. Liter, Omaha, Nebr., assignors to Burd & Fletcher Company, Kansas City, Mo., a corporation of Missouri Filed Apr. 9, 1965, Ser. No. 446,934 Claims. (Cl. 229-33) This invention relates to cartons and, more particularly, to a carton foldable from a blank formed froma single sheet of material, which carton is specifically adapted for quick sealing operations.

In a rectangular-type of carton, the lid or top panel will commonly be hingedly connected to one sidewall of the carton, and cover flaps will be provided which normally extend downwardly from the three free edges of the top panel, which cover flaps are adapted to be positioned in face-to-face relationship with the proximal outer surfaces of the container sidewalls and end walls. A heatactivated sealing agent or other adhesive is provided between the facing cover flaps and their corresponding sidewalls and end walls, and the agent is activated by passing the carton through a machine which, in the case of heat sealing, applies heat to respective pairs of facing flaps and walls to complete the sealing of the carton.

Thus, the sealing step must be performed three times, once on each set of cover flaps and corresponding walls, to finish the sealing process. Therefore, the machinery for this procedure must include mechanism for sequentially treating each of the three sealing surfaces of the carton, and this many times necessitates mechanical means for turning the carton toward the heating element or, as an alternative, the turning must be done manually.

The primary object of this invention is to provide acarton having multiple sealing surfaces thereon wherein all sealing operations may be performed in a single processing step to obviate the above discussed problems. To attain this object the cover flaps are provided with extensions which are engageable with a common surface on the carton, the extensions being scalable to the common surface by the performance of a single processing step. The sealing surfaces of the carton are adequately bonded to present a carton which will withstand rough handling and the like without attendant problems, such as inadvertent unsealing.

It is another object of the present invention to provide a carton having multiple sealing surfaces thereon wherein only a single adjustment of the sealing mechanism is necessary for each type of carton processed. In the conven-' tional carton heat-sealing operations discussed above, the heating element must be selectively positioned with respect to the carton-sealing surfaces whereby the heat will be properly applied to activate the sealing adhesive compound. Thus, the spacing of the heater element must be changed to accommodate the particular width and length of the carton as it is sequentially treated.

Since the carton of the present invention is processed in a single step, only one dimensional heating is necessary, this normally being equal to the height of the carton when the same is in its folded condition. In conventional apparatus, a plurality of heating elements could be used to avoid dimensional problems and each element would be spaced to accommodate a respective sealing surface on the carton as it is sequentially treated. This, of course, presents an economical problem since heating equipment is relatively expensive and consequently, any decrease in equipment, as afforded by the utilization of the instant carton, can substantially lower the over-all cost of the carton to the manufacturer.

Also to be considered in the economic aspect of the carton-sealing operation is that multiple heating units or the multiple use of a single unit on each carton, would result in relatively large electrical power requirements. To the contrary, our novel carton requires only one heating unit which performs a complete sealing operation in one step and hence, power requirements would be considerably lowered. Thus, from an economic standpoint, the present invention is advantageous with respect to speed of operation, less complicated machinery, and lower power consumption.

Yet another object of the instant invention is to pro vide a carton comprising a blank which is an initially flat, single sheet of foldable material having suitable cuts and score lines thereon, whereby the blank is foldable to present a carton having the above-described features. The present invention thus provides significant novel sealing and packaging advantages while maintaining the space saving, storing and shipping advantages of conventional folded cartons.

More specifically, the blank disclosed herein is foldable to present a generally rectangular carton having integral flaps for covering the sides and ends thereof, there being extensions on the ends of the cover flaps which will be disposable in face-to-face engagement with the bottom panel of the carton. The extensions are provided with heat-activated adhesive material on the inner surfaces thereof and thus, when a heating element is applied to the carton, the extensions will become bonded to the bottom panel to completely seal the carton in one processing step.

In the drawing:

FIGURE 1 is a perspective view of a carton made pursuant to the teachings of the instant invention, showing the same in a partially folded condition; and

FIG. 2 is a plan view of the blank from which the carton of the instant invention is made.

The carton of the present invention is constructed from a blank, broadly designated by the numeral 10, which is shown in FIG. 2 in its initially flattened condition. Blank 10 is formed from a suitable foldable material such as cardboard or the like, which may be easily cut and scored to facilitate the construction of the carton. Blank 10 and its composite parts have a normally inner surface 12 and a normally outer surface 14.

A substantially rectangular center section 16 is provided in blank 10 and has a plurality of transverse score lines 18, 20 and 22. Transverse score lines 18-22 form respectively an outer sidewall 24, a bottom panel 26, an inner sidewall 28, and atop panel 30.

A pair of locking tongues 32 are integrally and hingedly secured to each of sidewalls 24 and 28 by lines of bend 34. A pair of end walls 36 are integrally and hingedly secured to the opposed end edges of bottom panel 26 by line of weakness 38. A pair of locking slits 40 are provided in each end wall 36 for interlocking with corresponding locking tongues 32.

A pair of end cover flaps 42 are integrally and hinged ly secured to the opposed end edges of top panel 30 by fold lines 44, there being a front cover flap 46 similarly secured to the free side edge of top panel 30 by fold line 48. An extension 50 is hingedly secured to each of the end cover flaps 42 and front cover flap 46 in opposed, spaced relationship to top panel 30 by a line of fold 52.

Extensions 50 are of a relatively narrow width with respect to their corresponding cover flaps 42 and 46, and the opposed ends of each extension 50 are cut diagonally at approximately 45 to form a substantially trapezoidal member. An adhesive 54 is provided on the inner surface 12 of each extension 50, such adhesive being of any desired type, preferably a heat-activated material.

To construction the instant carton, end walls 36 are folded along lines of weakness 38 until they extend perpendicularly upwardly from bottom panel 26. Outer sidewall 24 is folded along score line 18 toward the upwardly extending end walls 36 and locking tongues 32 of outer sidewall 24 are simultaneously folded along lines of bend 34 toward end walls 36. The inner surface 12 of each locking tongue 32 of outer sidewall 24 is disposed in faceto-face relationship with the outer surface 14 of end wall 36 and slipped therealong until tongue 32 interlocks with a corresponding slit 40, The interlocking of tongues 32 and slits 40 is shown in perspective in FIG. 1.

Inner sidewall 28 is secured to end walls 36 in a manner identical to outer sidewall 24. After sidewalls 24 and 28 have been interlocked with end walls 36, a substantially rectangular receptacle is formed with the respective end and sidewalls extending perpendicularly upwardly from bottom panel 26. The desired contents of the carton may then be placed within the receptacle.

Top panel 30 is folded along score line 22 until it engages the uppermost edge of end walls 36 and outer side wall 24 to complementally overlie bottom panel 26. Cover flaps 42 and 46 are folded along respective fold lines 44 and 48 until the inner surfaces 12 thereof are in face-toface engagement with the outer surfaces 14 of corresponding end walls 36 and outer sidewall 24. The normally vertical dimensions of cover flaps 42 and 46 are substantially equal to the normally vertical dimensions of end walls 36 and outer sidewall 24, whereby, when the cover flaps are in the aforementioned face-to-face relationship, lines of fold 52 extend longitudinally adjacent to corresponding edges of bottom panel 26.

Extensions 50 may then be folded along lines of fold 52 until the inner surfaces thereof are in face-to-face engagement with the outer surface 14 of bottom panel 26. Extensions 50 do not overlap each other due to the provision of the diagonal cuts in the opposed ends thereof.

When folding is completed, as indicated in FIG. 1 except for the end cover flap 42, adhesive 54 is disposed between the inner surfaces 12 of extensions 50 and the proximal outer surface 14 bottom panel 26, If adhesive 54 is a heat-activated type of material, an electrical heating element may be applied to the bottom of the carton to activate adhesive 54 and securely bond extensions 50 to bottom panel 26.

Thus, it will be appreciated that the carton is completely sealed by a single processing step, this normally being a heat-sealing operation. On the contrary, conventional cartons are not provided with extensions 50 and thus a complete sealing operation will necessitate sequentially securing each of the cover flaps to corresponding end and sidewalls. For example, in the illustrated carton, if extensions 50 were not provided, the respective cover flaps 42 and 46 would individually be sealed to corresponding end Walls 36 and outer sidewall 24, and thus it would be necessary to apply the heating element 32 in three separate steps to completely seal the carton.

Therefore, the utilization of extensions 50 reduces the number of applications of the heating element to the carton with a resulting decrease in electrical power requirements. Also, the use of the present invention will reduce the amount of machinery required for sealing operations since it will not be necessary to sequentially turn the carton to present the respective sealing surfaces to the heating element. It may also be necessary to adjust the electrical heating element to accommodate the length and width of conventional cartons to seal the respective end and front cover flaps, while a single setting, i.e., the height, is sufficient when utilizing the carton of the present invention.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is;

l. A carton comprising:

a bottom panel having an inner and an outer surface;

sidewalls normally extending upwardly from said bottom panel;

a top panel connected to one of said sidewalls and positioned in overlying relationship to said bottom panel;

a plurality of cover flaps depending from said top panel;

and

an extension on each of said flaps, said extensions each being secured to the outer surface of said bottom panel.

2. The invention of claim 1, said flaps including a front cover flap and a pair of opposed end cover flaps.

3. The invention of claim 1, said extensions being of a width less than their corresponding flaps.

4. A carton comprising;

a rectangular bottom panel having an inner and an outer surface;

a pair of sidewalls normally extending upwardly from respective side edges of said panel;

a rectangular top panel hingedly secured to one of said sidewalls and positioned in overlying relationship to said bottom panel;

a plurality of cover flaps depending from said top panel;

and

an extension on each of said flaps, said extensions being secured to the outer surface of said bottom panel.

5. The invention of claim 4, there being a pair of end walls extending upwardly from respective end edges of said bottom panel.

6. The invention of claim 5, there being a pair of end cover flaps and a front cover flap.

7. The invention of claim 6, said cover flaps being positioned in overlying relationship to proximal end and sidewalls in face-to-face engagement therewith.

8. A carton formed from a single, initially flat blank of foldable material having a normally inner and outer surface, said blank comprising:

a substantially rectangular, center section having a plurality of transverse score lines thereon to form respectively an outer sidewall, bottom panel, inner sidewall, and top panel;

a pair of end walls secured to the opposed end edges of said bottom panel; 7

a plurality of cover flaps hingedly secured to the free edges of said top panel;

an extension hingedly secured to each of said cover flaps in opposed, spaced relationship to said top panel, said blank being folded to form a closed carton, said cover flaps and extensions being swung to a position whereby said extensions are in overlying relationship to the outer surface of said bottom panel, said extensions being secured to said outer surface to hold the carton in its folded position.

9. The invention of claim 8, there being a pair of end cover flaps and a front cover flap.

10. The invention of claim 8, one face of each of said extensions being in face-to-face relationship with the outer surface of said bottom panel, when said extensions are in said secured condition.

References Cited UNITED STATES PATENTS 1,092,528 4/1914 Hopkins et al. 229-36 1,144,130 6/1915 Hummel 22943 1,252,002 1/1918 Hale 229-43 X 2,983,420 5/1961 Rellstab 22936 X FOREIGN PATENTS 956,507 4/ 1964 Great Britain.

JOSEPH R. LECLAIR, Primary Examiner.

D. F. NORTON, Assistant Examiner. 

1. A CARTON COMPRISING: A BOTTOM PANEL HAVING AN INNER AND AN OUTER SURFACE: SIDEWALLS NORMALLY EXTENDING UPWARDLY FROM SAID BOTTOM PANEL; A TOP PANEL CONNECTED TO ONE OF SAID SIDEWALLS AND POSITIONED IN OVERLYING RELATIONSHIP TO SAID BOTTOM PANEL; A PLURALITY OF COVER FLAPS DEPENDING FROM SAID TOP PANEL; AND AN EXTENSION ON EACH OF SAID FLAPS, SAID EXTENSIONS EACH BEING SECURED TO THE OUTER SURFACE OF SAID BOTTOM PANEL. 